Lycamobile users face service disruption following a cyber-attack – here's what you need to know

Lycamobile – which piggybacks off EE's network – has admitted it's currently experiencing some network issues following the cyber-attack, which it says it's "working hard" to restore. The disruption appears to have started on Friday 29 September with some customers reporting being unable to top up, make calls, send texts or access mobile data.

Some Lycamobile users are also reporting that they've been unable to request 'PACs' (porting authorisation codes), which allow them to transfer their number to another network.

Lycamobile was unable to confirm to us exactly which services are affected, how many customers are impacted and when the problems will be resolved. We'll update this story as soon as we know more.

Lycamobile hasn't yet confirmed what, if any, data has been accessed

Lycamobile is yet to reveal the extent of the data breach, and it's still working with external IT security experts to "urgently investigate whether any personal information may have been compromised". Lycamobile has also said it will "keep customers updated on the outcome of our investigation".

In the meantime, it's best to remain alert for suspicious activity and to change your password if you use your Lycamobile account login for other online accounts. Our Stop scams guide has full info, but in brief:

• Watch out for phishing emails. Criminals may use your personal details to target you with convincing emails, texts and calls. Be suspicious of unsolicited requests for your personal or financial details. If you receive an email which you’re not sure about, forward it to the Suspicious Email Reporting Service (SERS) at report@phishing.gov.uk.

• Monitor your bank account. Be vigilant against any unusual activity on your accounts and report any unauthorised transactions to your bank immediately.

• Secure your passwords. If you use your Lycamobile password for other online accounts, you should change it now. As a form of best practice, you may also want to consider changing passwords for important accounts, such as banking. See Cyber Aware's advice on creating a good password that you can remember, or read the National Cyber Security Centre's (NCSC’s) guidance for help on using a password manager and its info on how to protect yourself from the impact of data breaches.

• If you think you've been a victim of fraud, report it. If you have been a victim of fraud or cyber crime as a result of a data breach, contact your bank immediately and report it to Action Fraud online or by calling 0300 123 2040.

Lycamobile problems: 'I can't make a call or send an SMS – what's wrong?'

Some Lycamobile users have complained of various problems on social media, as well as on the MSE Forum, over the past few days:

If you're affected, you can complain

If your mobile services aren't working due to the outage, you can complain. Under rules from regulator Ofcom, you may be entitled to a refund or account credit if you suffer long periods without service.

You can reach Lycamobile's customer services by dialling 322 – though some users have reported that this number isn't currently working. Alternatively, you can try Lycamobile's chatbot, which is available on its contact page.

If you want to make a formal complaint, you'll need to complain to Lycamobile directly on complaints@lycamobile.co.uk or by sending it a letter at:

Complaints Department,Lyca Mobile UK Limited,3rd Floor, Walbrook Building,195 Marsh Wall,London,E14 9SG.

If you're unhappy with Lycamobile's final response after eight weeks, you can take your complaint to its alternative dispute resolution provider Cisas.

You can also make a complaint to the regulator Ofcom via its monitoring form. Ofcom won't reply to individual complaints, but it may investigate a company if it thinks there's a problem.

Still unhappy? You may be able to leave penalty-free...

Lycamobile offers pay-as-you-go deals and 30-day rolling contracts, as well as some 12-month contracts.

• On a pay-as-you-go or a 30-day rolling contract? You're free to switch to a new provider penalty-free at any point, though bear in mind we're seeing users report problems requesting a PAC, which is needed if you want to transfer your number to a new provider.

  If you're on a 30-day rolling contract, you'll need to cancel your auto-renewal. You can do this online in your 'My Lycamobile' account, or by dialling *190# and entering 1 to confirm the cancellation.

  With pay-as-you-go, simply run down the credit, turn off 'auto top up' if you use it, and stop using the Sim or port it to a new firm.

  If you switch partway through a 30-day contract or pay-as-you-go bundle, you'll lose any unused days and won't get a refund.

• On a 12-month plan? Here, you can't cancel penalty-free. However, it's worth putting a formal complaint to Lycamobile (as outlined above).

If you're thinking of leaving Lycamobile, you can use our Cheap Mobile Finder tool to find the best deal for you.

What does Lycamobile say?

Lycamobile said: "Our focus on our customers is paramount. We are working around the clock to ensure that the impact on them is minimised."